The myocyte shortening (% of diastoliccell length) is dose-dependent with IGF-1, peaking at 150–300 ng/mL [64].Furthermore, structural changes like LVH and fibrosis in acromegaly puts thepatient at risk for arrhythmias, as collagen deposition in the cardiac tissue isalso associated with cardiac rhythm disorders [65]. This evidence concerns the gene IGF1 and acromegaly.